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Synonyms

question mark

American  
[kwes-chuhn mahrk] / ˈkwɛs tʃən ˌmɑrk /

noun

  1. Also called interrogation point.  Also called interrogation mark.  a punctuation mark indicating a question: usually, as in English, the mark (?) placed after a question.

  2. something unanswered or unknown.

    His identity is still a question mark to most of us.

  3. an anglewing butterfly, Polygonia interrogationis, having a silver marking that resembles a question mark on the underside of each hindwing.


question mark British  

noun

  1. the punctuation mark ? , used at the end of questions and in other contexts where doubt or ignorance is implied

  2. this mark used for any other purpose, as to draw attention to a possible mistake, as in a chess commentary

  3. an element of doubt or uncertainty

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

question mark Cultural  
  1. A punctuation mark (?) that follows a direct question: “Is Ralph really seven feet tall?”


Etymology

Origin of question mark

First recorded in 1865–70